A SPATIO-TEMPORAL ANALYSIS OF VELOCITY FIELDS IN THE SOLAR PHOTOSPHERE.
Abstract
A series of high (spatial) resolution spectrograms were taken of the center of the solar disk at Kitt Peak National Observatory, U.S.A. The spectrograms were taken every 20 seconds for 55 minutes. The Doppler shifts of the absorption lines, as well as the intensity fluctuations, both in the continuum and in the lines, were subjected to a simultaneous spatial and temporal Fourier analysis. The results are displayed in the form of contour lines k - omega plane, or diagnostic diagram. These results clearly show convective overshoot at all levels of the photosphere. They also show that the well known 5 minute oscillations are primarily standing resonant acoustic waves. The 'gravity wave' mode was not observed. Arguments are presented suggesting that the oscillations are not formed directly from the 'piston action' of a convective cell impinging on the stable photosphere, but rather are formed within the convection zone itself. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 24, 1968
- Accession Number
- AD0666621
Entities
People
- Edward N. Frazier
Organizations
- University of California, Berkeley